Sutter's Mill was a water-powered sawmill on the bank of the South Fork American River in the foothills of the Sierra Nevada in California. It was named after its owner John Sutter. A worker constructing the mill, James W. Marshall, found gold there in 1848. This discovery set off the California Gold Rush (1848–1855), a major event in the history of the United States.

The South Fork American River is a major tributary of the American River in El Dorado County, California, draining a watershed on the western slope of the Sierra Nevada east of Sacramento. The river begins in pristine Desolation Wilderness and flows through the Sierra Nevada foothills. The river at Coloma was the site of James Marshall's discovery of gold at Sutter's Mill on January 24, 1848, which started the California Gold Rush. The South Fork of the American is "the most popular recreation stream in the West" for whitewater rafting in North America, e.g., 80,000 visitors in 2011. Professional whitewater rafting companies have been offering commercial rafting trips on the South Fork American River since 1978.